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Questions in chemistry

[Done] A 4 kg rock is rolling at 10 m/s. Find its kinetic energy.

[Done] Describe the primordial soup theory.

[Done] Within a period, an increase in atomic number is usually accompanied by A. a decrease in atomic radius and an increase in electronegativity. B. an increase in atomic radius and an increase in electronegativity. C. a decrease in atomic radius and a decrease in electronegativity. D. an increase in atomic radius and a decrease in electronegativity. E. None of these answer choices is correct.

[Done] Determine the number of electrons in the outer ring (valence electrons) for each of the following elements: - Phosphorus - Potassium - Oxygen - Iodine - Gold - Bromine - Sulfur - Cobalt

[Done] The change in heat energy for a reaction is best expressed as a change in: A. Enthalpy (H) B. Absolute temperature (T) C. Specific heat (c) D. Entropy (S) E. Kinetic energy (KE)

[Done] Bicarbonate ion is an example of a: a. an acid b. a base c. an acidic salt d. a basic salt e. an amphoteric substance

[Done] These two compounds are in the liquid phase at 293 K. A. Br₂ and Hg B. Cl₂ and F₂ C. NH₄⁺ and H₃O⁺ D. Fe and Co E. Diamond and graphite

[Done] Pick the answer that most likely represents the substances’ relative solubilities in water. A. CH₃CH₂CH₂CH₃ < CH₃CH₂CH₂OH < HOCH₂CH₂OH B. CH₃CH₂CH₂OH < CH₃CH₂CH₂CH₃ < HOCH₂CH₂OH C. CH₃CH₂CH₂CH₃ < HOCH₂CH₂OH < CH₃CH₂CH₂OH D. HOCH₂CH₂OH < CH₃CH₂CH₂OH < CH₃CH₂CH₂CH₃ E. HOCH₂CH₂OH < CH₃CH₂CH₂OH < CH₃CH₂CH₂CH₃

[Done] Which formula represents a compound whose molecules are tetrahedral? A. BH₃ B. C₂H₂ C. CH₄ D. H₂O E. C₂H₆

[Done] How many 100 mg tetracycline capsules can be made from 1 kg of tetracycline? A. 10 B. 100 C. 1,000 D. 10,000 E. 100,000